HIGH STRENGTH TITANIUM ALLOY ENGINE VALVE FOR AUTOMOBILE

摘要

PROBLEM TO BE SOLVED: To provide a high strength titanium alloy engine valve for automobile excellent in strength, fatigue strength and hot workability, and having sufficient wear resistance.;SOLUTION: This engine valve for automobile is made of titanium alloy which contains Al of 4.4 wt.% or more and 5.5 wt.%, Fe of 1.4 wt.% or more and 2.3 wt.% and Mo of 1.5 wt.% or more and 5.3 wt.%, and satisfies conditions of impurities that Si is less than 0.1 wt.% and C is less than 0.01 wt.%, and of which remaining is titanium and unavoidable impurities. Oxidized hardened layer is formed on a part or whole of a surface of the engine valve, is coated by hard coating or is applied to peening process.;COPYRIGHT: (C)2007,JPO&INPIT